Sleeve-type carriers are commonly used to package beverage cans. Such a carrier is typically formed from a paperboard blank which is opened into sleeve form by a packaging machine, after which the cans are introduced and the end panels folded and glued together. The resulting package completely encloses the cans and has a handle incorporated into the top panel to allow a user to more readily lift and carry the package.
Many different handle designs for sleeve-type packages have come into use over the years, probably the most common being the suitcase type of handle. This comprises two handle openings in the top panel extending lengthwise of the carrier and being spaced from each other so that the top panel portion between them forms a strap. The carrier is lifted by inserting the fingers in one of the openings and lifting up on the strap portion. One problem with this design is that the edges of the strap are often uncomfortable to the hand of the user, particularly if the package is carried for any length of time. Another is that the concentration of lifting stresses at the ends of the strap has necessitated the use of relatively thick paperboard to prevent tearing at these locations.
To overcome these problems it has been suggested to employ a transversely extending handle instead. Such a handle comprises a transverse opening in the top panel of the carrier through which the fingers are inserted. By then lifting up on the top panel the package can be lifted and carried more comfortably. Despite this result, such packages still are in need of improvement in the area of stress distribution. If no provision is made, such as in the handle arrangement disclosed in U.S. Pat. No. 2,718,301, issued to F. D. Palmer, the package is susceptible to tearing at the ends of the handle opening. Since the only way to prevent tearing in a design such as Palmer's is to use relative thick paperboard, the production costs increase as a result.
To combat the tendency to tear, the carrier disclosed in U.S. Pat. No. 4,558,816, issued to P. J. Wood, incorporates a slit that extends into the side panels of the carrier and also contains a series of fold lines connected to the slit. This arrangement is for the purpose of distributing the lifting stresses generated when the package is lifted by its handle. Even this design, however, permits more concentration of lifting stresses adjacent the ends of the transverse slit than desired, forcing relatively rigid design parameters to be followed and causing the top panel to be pulled up too abruptly when lifted.
It would be desirable to provide a carrier having a transverse handle design which would allow a reduction in the caliper of the paperboard without resulting in an excessively flexible handle structure.